Data reproducing apparatus, content management method, program, and storage medium

ABSTRACT

A data reproducing apparatus comprises: a reproducing unit adapted to read out data from a plurality of recording media; a list generating unit adapted to generate a content list which describes storage location information in association with contents stored in the plurality of recording media; and a communication unit adapted to communicate with an external device and sending the content list to the external device, wherein the list generating unit checks if the contents stored in the plurality of recording media include identical contents, and if the identical contents are detected, the list generating unit generates the content list including information indicating that the storage location information of the identical contents are integrated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a data reproducing apparatus forreproducing a content stored in a recording medium by an image capturingapparatus such as a digital camera or the like, and a content managementmethod.

2. Description of the Related Art

In image capturing apparatuses such as digital still cameras, digitalvideo cameras, and the like, since a recordable data size dramaticallyincreases with increasing number of pixels of image capturing elements,the capacities of recording media that is available for use in the imagecapturing apparatuses have increased accordingly. Also, a plurality ofstorages can be used to attain a large capacity, and a method that usesa large-capacity external storage device connected via a digitalinterface in addition to a recording medium that uses an internal slotof the image capturing apparatus is prevalent.

Recent image capturing apparatuses can use external storage devices suchas a hard disk (HDD) and the like via a high-speed serial interface suchas Universal Serial Bus (USB), IEEE1394, and the like simultaneouslywith internal recording media such as a memory card, disk, tape, and thelike.

FIG. 1 shows an arrangement in which a digital camera 101 that uses arandom access medium 102 as a recording medium and an external storagedevice 104 are connected via a USB interface cable 103. Both the digitalcamera 101 and external storage device 104 comprise USB interfaces, as amatter of course.

The digital camera 101 serves as a USB host, and the large-capacityexternal storage device 104 serves as a USB device (slave). When the USBhost acquires data from the USB device via the USB interface, it is acommon practice to make communications according to the standards suchas PTP, Mass Storage, and the like. Note that PTP is a standardspecified by “Universal Serial Bus Still Image Capture Device DefinitionRevision 1.0 Jul. 11, 2000”. Also, Mass Storage is a standard specifiedby “Universal Serial Bus Mass Storage Class Bulk-Only Transport Revision1.0 Sep. 31, 1999”.

A case of communications compliant to Mass Storage will be explainedbelow with reference to FIG. 1.

Upon detecting the connection of the external storage device 104 via theUSB interface cable 103, the digital camera 101 acquires descriptorinformation from the external storage device 104. The digital camera 101determines device information and a communication method, and recognizesthe external storage device 104 as a device of Mass Storage Class. Afterthat, the digital camera 101 acquires data according to Mass Storage. Inthis case, the digital camera 101 accesses all image data stored in theexternal storage device 104 via its internal file system.

The digital camera 101 also connects the random access medium 102 as astorage, and allows the user to display and browse image data via itsinternal file system. The user manipulates the digital camera 101 todesignate a storage used to save and browse captured image data, and canalso record the same image in a plurality of storages at the same time.The user individually designates the random access medium 102 andexternal storage device 104, thus freely manipulating saved image data.

With digital devices, it is a common practice to back up data and tocontrol respective devices via a network. Consumer devices such as adigital still camera, digital video camera, and the like are alsoconnected to the network and can communicate with external devices.Especially, by building up an IP network using an Internet Protocol (tobe abbreviated as IP hereinafter), many devices are connected to eachother and can exchange data. For example, in some system, the user canbrowse, via a personal computer (to be abbreviated to as PC hereinafter)or the like, moving image data stored in one external storage devicesuch as a home server or the like connected to a tuner by converting themoving image data into a displayable format according to each externaldevice (for example, Japanese Patent Laid-Open No. 2005-065008).

Like in the home server, the user can also browse image data stored in adigital still camera using an external device via the network. Digitaldevices undergo extensions such as support of interfaces that allow IPconnections such as Ethernet®, Wireless LAN, and the like in addition toa serial bus network such as USB, IEEE1394, and the like. By providing,in a common format, an image designated by an acquisition request froman external device, images can be displayed on the external device.

However, upon issuing an acquisition request of a plurality of imagesstored in a plurality of recording media in addition to the designatedimage, if the plurality of recording media store identical images, theexternal device acquires all images including the identical images.Also, the external device displays the identical images simultaneouslystored in the plurality of recording media. For this reason, when theuser visually confirms images displayed on a display of the externaldevice, he or she cannot discriminate their differences, resulting inconfusion. Especially, when the external device adopts a display methodthat does not show image file names, attributes, and the like, aplurality of identical images are acquired, thus requiring a long timeto acquire and display data.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of theaforementioned problems, and has as its object to implement a techniquethat can efficiently provide contents to an external device bycentralized management of identical contents stored in a plurality ofstorages.

According to the present invention, there is provided a data reproducingapparatus comprising: a reproducing unit adapted to read out data from aplurality of recording media; a list generating unit adapted to generatea content list which describes storage location information inassociation with contents stored in the plurality of recording media;and a communication unit adapted to communicate with an external deviceand sending the content list to the external device, wherein the listgenerating unit checks if the contents stored in the plurality ofrecording media include identical contents, and if the identicalcontents are detected, the list generating unit generates the contentlist including information indicating that the storage locationinformation of the identical contents are integrated.

According to the present invention, there is provided a contentmanagement method in a data reproducing apparatus, which comprises areproducing unit adapted to read out data from a plurality of recordingmedia, a list generating unit adapted to generate a content list whichdescribes storage location information in association with contentsstored in the plurality of recording media, and a communication unitadapted to communicate with an external device and sending the contentlist to the external device, the method comprising: a step of checkingif the contents stored in the plurality of recording media includeidentical contents; and a step of generating the content list includinginformation indicating that the storage location information of theidentical contents are integrated, when the identical contents aredetected.

According to the present invention, contents can be efficiently providedto an external device by centralized management of identical contentsstored in a plurality of storages.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing the arrangement in which a digital camera andexternal storage device are connected;

FIG. 2 is a view showing a content management system according to oneembodiment of the present invention;

FIG. 3 is a block diagram showing the internal arrangement of a digitalcamera according to the embodiment of the present invention;

FIG. 4 is a flowchart showing the content list generation process by thedigital camera;

FIG. 5 shows an example of a management file list according to theembodiment of the present invention;

FIG. 6 shows an example of a content list according to the embodiment ofthe present invention; and

FIG. 7 is a sequence chart executed when a PC acquires contents storedin the digital camera.

DESCRIPTION OF THE EMBODIMENTS

The best mode of carrying out the present invention will be described indetail hereinafter with reference to the accompanying drawings.

Note that the embodiments to be described hereinafter are examples topractice the present invention and should be appropriately modified orchanged depending on the apparatus arrangement and various conditions towhich the present invention is applied. Hence, the present invention isnot limited to the following embodiments.

[System Arrangement]

FIG. 2 shows a content management system according to one embodiment ofthe present invention.

Referring to FIG. 2, reference numeral 201 denotes a digital camera asan image capturing apparatus, which can detachably receive, as internalrecording media, a CF (CompactFlash®) memory card 202 and SD™ (SecureDigital) memory card 203. Also, the digital camera 201 can connect ahard disk 204 as an external storage device via a USB interface cable.

The digital camera 201 is connected to a hub 205 via an Ethernet cableto form an IP network with a PC 206. The digital camera 201 implementsdata exchange, device control, and the like according to a commandprotocol on the IP network. As the command protocol on the IP network, acontrol command system defined by UPnP™ or DLNA (Digital Living NetworkAlliance) can be used.

This embodiment is premised on a server-client type command system inwhich the digital camera 201 (i.e., a data reproducing apparatus)returns responses to command requests from the PC 206. However, thepresent invention does not always require such specific command system.For example, the present invention can be practiced using othercommunication systems as long as protocols that can exchange data andcommands are used.

FIG. 3 is a block diagram showing the internal arrangement of thedigital camera 201.

Referring to FIG. 3, a main control unit 301 systematically controlscommunication processing, image capturing processing, displayprocessing, recording processing, and reproducing processing by thedigital camera. An image capturing unit 302 mainly executes processesfrom when the user presses a trigger button until generation of an imageto be handled as digital data, and issues recording and reproducinginstructions to a recording medium connected or attached to a recordingand reproducing unit 305.

The recording and reproducing unit 305 can receive, for example, a CFmemory card 310 and SD memory card 311 as recording media. Furthermore,the recording and reproducing unit 305 can connect a hard disk (HDD) 312via USB. Note that both the recording and reproducing unit 305 and harddisk 312 include USB interfaces. The aforementioned recording media,i.e., the CF card 310, SD card 311, and hard disk 312 serve as storagesof image data and the like.

A display control unit 304 displays captured images, and also operationmenus, alarm messages, and the like to the user.

A communication control unit 306 executes protocol control and dataexchange upon making communications with external devices. Thecommunication control unit 306 includes an Ethernet interface. A contentmanaging unit 303 generates a content list based on contents of therespective recording media read out by the recording and reproducingunit 305, and temporarily records the content list on a temporarystorage medium 315. The content managing unit 303 sends response data inresponse to a content list sending request or content reproducingrequest from an external application.

The digital camera 201 can simultaneously record contents such ascaptured images and the like on a plurality of recording media. In thiscase, the recording media are not related to each other, and only thedigital camera 201 can recognize the contents on the recording media.

The content list generating processing by the digital camera 201 will bedescribed below.

FIG. 4 is a flowchart showing the content list generation process by thedigital camera 201. In this embodiment, a content list is generated atthe camera start-up timing. In addition to the camera start-up timing, acontent list may be generated when the connection with the recordingmedia or external device has changed, i.e., at the connection timingwith an external device, at the connection timing with a recordingmedia, at a specific content generation timing, or the like. In any ofthese cases, the object of the present invention can be achieved.

Referring to FIG. 4, after initialization of respective hardware modulesaccording to an instruction from the main control unit 301 at the camerastart-up timing, the content managing unit 303 clears a content listrecorded in the temporary storage medium 315 (S401).

The recording and reproducing unit 305 checks if the recording media 310to 312 are attached (connected) (S402). If at least one of theserecording media is attached (YES in S402), the unit 305 detects if thatrecording medium includes a content that can be handled by the digitalcamera (S403). If the recording medium includes a content that can behandled (YES in S403), the content managing unit 303 starts content listgeneration process after a content search and the like. If there is nocontent that can be handled (NO in step S403), the unit 303 immediatelygenerates a content list indicating that no content is found (S409).

If the recording medium includes a content that can be handled (YES instep S403), the content managing unit 303 acquires information such asthe amount of contents, access speed, and the like for each recordingmedium from a management file list in the file system of the digitalcamera, prior to generation of a content list. FIG. 5 shows an exampleof the management file list. Furthermore, the unit 303 acquiresidentification information (file names, file sizes, file generation dataand time, and the like) of contents recorded in each recording medium.The unit 303 conducts a content search based on various kinds ofacquired information (S404).

The content managing unit 303 determines a recording medium including alargest amount of contents as a base storage in content list generation(S405). When a plurality of recording media include the same amount ofcontents, the unit 303 preferentially selects a recording media with ahighest access speed as a base storage. Furthermore, when a plurality ofrecording media have the same amount of contents and the same accessspeed, the unit 303 selects a recording medium having a larger freecapacity or total capacity as a base storage. In the management filelist shown in FIG. 5, since “External HDD” has a largest amount ofcontents 501 compared to other media, the unit 303 generates a contentlist to have “External HDD” as a base storage. After the base storage isdetermined, the unit 303 searches for contents to be registered in acontent list based on the base storage.

Next, the content managing unit 303 checks for each individual contentif an identical content is stored in the plurality of recording media,based on the acquired content identification information, i.e., bycomparing information such as file names, file sizes, and header files(S406). If the unit 303 determines in step S406 that the same content isstored in the plurality of different recording media (YES in S406), itappends, to the content list, a content overlap mark which indicatesthat an identical content is recorded in a plurality of recording media(S407).

When the identical content is recorded in a plurality of recordingmedia, the content managing unit 303 registers a recording medium with ahighest access speed in a recording medium column that represents thestorage location of the corresponding content to be registered in thecontent list. For example, assume that files of an identical content arerespectively recorded in all storages described in the management filelist in FIG. 5 (contents overlap). In this case, since “CF card” has ahighest access speed 502 compared to other media, the unit 303 registers“CF card” as the recording medium of the storage location of theoverlapping content.

If an identical content is stored in no other recording media (NO inS406), the content managing unit 303 registers original information ofthat content in the content list. Upon completion of contents in thebase storage, the unit 303 additionally registers contents in otherstorages in the list (S408).

In this way, by repeating the process of checking if each recordingmedium stores a content identical to that stored in another medium, thecontents recorded in the respective recording media can be fullychecked. Finally, if there is no more content to be added in step S403,the content managing unit 303 generates a content list in which all thecontents have already been registered (S409).

The content list is generated for only recording media attached orconnected at that time. Hence, if it is determined in step S402 that norecording medium is attached (connected) (NO in step S402), the contentmanaging unit 303 skips generation of a content list. When the contentlist is updated at a timing other than the camera start-up timing, theunit 303 updates the list only for a recording medium or contents whoserecorded data are updated, and does not execute any processing such as asearch and the like for other content list.

FIG. 6 shows an example of the generated content list. The contentmanaging unit 303 manages respective contents by storing data in columnsof an ID (identification information) 601 and content name 602 incorrespondence with each other. In response to an acquisition request orthe like from an external application using an ID-based protocol such asPTP or the like, required information is received based on this ID.

Especially, when contents overlap in respective recording media, thecontent managing unit 303 appends an “Integrated Flag” 604 as thecontent overlap mark, and describes all pieces of storage locationinformation of contents in a column of a content path 603. In a columnof a download path 605 which represents the recording medium as thestorage location upon reception of a sending request from an externalapplication or the like and reading out content data, the unit 303describes a path indicating a content in a storage with a highesttransfer speed (e.g., CF card) as a base recording medium. Upon sendingthe content data to an external application, the unit 303 removes aconversion table of the content path 603 from the content list, thusallowing the external application to display the content list.

Also, the content list can be sorted based on a content generation dateand time 606, file size 607, and the like.

FIG. 7 shows the sequence when the PC 206 acquires a content stored inthe digital camera 201.

As shown in FIG. 7, the digital camera 201 generates the content list bythe procedure described with reference to FIG. 4 at the start-up timing,and records the content list in the temporary storage medium 315 insidethe camera (S701).

When the PC 206 establishes a connection to the digital camera 201 to beable to communicate with each other, an application on the PC 206 sendsa content list acquisition request to the digital camera 201 (S702).

When the digital camera 201 receives the content list acquisitionrequest from the PC 206 via the communication control unit 306, the maincontrol unit 301 interprets the command, and sends the content listrecorded in the temporary storage medium 315 to the PC 206 (S703). Uponreception of the content list on the PC 206, the application of the PC206 generates and displays a user interface (UI) window using thecontent list (S704). The user selects a predetermined content from theUI window displayed on the PC 206 (S704), and sends a contentacquisition request to the digital camera 201 (S705).

When the digital camera 201 receives the content acquisition requestfrom the PC 206 via the communication control unit 306, the main controlunit 301 interprets the command, and the content managing unit 303determines the storage location of the content of interest using theconversion table of the content list. Furthermore, the recording andreproducing unit 305 reads out data from the recording medium as thedetermined storage location (S706). After that, the readout content datais sent to the PC 206 (S707).

Upon sending data to the PC 206, since the digital camera 201 reads outcontent data, which overlaps in a plurality of recording media, from therecording medium with the highest access speed, reception, display, andthe like at the PC 206 can be quickly made.

In case of an application which designates the recording medium anddisplays content data on the PC 206 side, if the user can refer to theoverlap mark 604 and content path 603 of the content list, he or she canavoid an identical content from being repetitively acquired. For thisreason, the need for troublesome data exchange operations required todisplay a content can be eliminated, thus improving operability.

Other Embodiments

The preferred embodiments of the present invention have been explainedusing their practical examples, and the present invention can bepracticed in the forms of a system, apparatus, method, program, storagemedium (recording medium), and the like. More specifically, the presentinvention can be applied to either a system constituted by a pluralityof devices, or an apparatus consisting of a single equipment.

The objects of the present invention can be achieved by implementingsome of the illustrated functional blocks and operations by eitherhardware circuits or software processing using a computer.

Note that the present invention includes a case wherein the invention isachieved by directly or remotely supplying a program of software thatimplements the functions of the aforementioned embodiments to a systemor apparatus, and reading out and executing the supplied program code bya computer of that system or apparatus. In this case, a computer of thesystem or the like reads out and executes the program code.

Therefore, the program code itself installed in a computer to implementthe functional processing of the present invention using the computerimplements the present invention. That is, the present inventionincludes the computer program itself for implementing the functionalprocessing of the present invention.

In this case, the form of program is not particularly limited, and anobject code, a program to be executed by an interpreter, script data tobe supplied to an OS, and the like may be used as long as they have theprogram function.

As a recording medium (storage medium) for supplying the program, forexample, a flexible disk, hard disk, optical disk, magneto-optical disk,and the like may be used. In addition, MO, CD-ROM, CD-R, CD-RW, magnetictape, nonvolatile memory card, ROM, DVD (DVD-ROM, DVD-R), and the likemay be used.

As another program supply method, connection can be established to ahome page on the Internet using a browser on a client computer, and thecomputer program itself of the present invention can be downloaded fromthe home page. Also, the program can be supplied by a compressed filecontaining an automatic installation function from the home page onto arecording medium such as a hard disk or the like. Also, the program codethat forms the program of the present invention may be segmented into aplurality of files, which may be downloaded from different home pages.That is, the present invention includes a WWW server which makes aplurality of users download a program file required to implement thefunctional process of the present invention by a computer.

Also, a storage medium such as a CD-ROM or the like, which stores theencrypted program of the present invention, may be delivered to theuser, and the user who meets a predetermined condition may be allowed todownload key information that decrypts the program from a home page viathe Internet. In this case, the user executes the encrypted programusing that key information to be installed on a computer, thusimplementing the present invention.

The functions of the aforementioned embodiments may be implemented notonly by executing the readout program code by the computer but also bysome or all of actual processing operations executed by an OS or thelike running on the computer on the basis of an instruction of thatprogram.

Furthermore, the functions of the aforementioned embodiments may beimplemented by some or all of actual processes executed by a CPU or thelike arranged in a function expansion board or a function expansionunit, which is inserted in or connected to the computer, after theprogram read out from the recording medium is written in a memory of theexpansion board or unit.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2006-286882, filed Oct. 20, 2006, which is hereby incorporated byreference herein in its entirety.

1. An image capturing apparatus comprising: a connection unit adapted todetachably connect a plurality of recording media which includes atleast one of internal recording media and at least one of externalrecording media, the internal recording media and the external recordingmedia having various access speeds; an image capturing unit adapted tocapture an object and generate image data of the object; a recording andreproducing unit adapted to record the image data in the plurality ofrecording media, and read out the image data from the plurality ofrecording; a list generating unit adapted to generate a content listwhich describes a list of image data stored in the plurality ofrecording media, and describes, in the list, storage locationinformation of each image data stored in the plurality of recordingmedia; and a communication unit adapted to communicate with an externaldevice and send the content list to the external device, wherein saidlist generating unit checks if the image data stored in the plurality ofrecording media include identical image data, and if the identical imagedata are detected, said list generating unit generates the content listwhich is registered as a representative storage location information bywhich the storage location information of the identical image data areintegrated with one piece of storage location information from among thestorage location information of the identical image data stored in theplurality of recording media, wherein the representative storagelocation information indicates a download path to download the identicalimage data stored in the plurality of recording media at the highestspeed.
 2. The apparatus according to claim 1, wherein the content listincludes a content name, a content generation date and time, a datasize, information of a recording medium as a storage location, saidcommunication unit sends the content list upon reception of a sendingrequest of a content list from the external device, and saidcommunication unit, which receives a sending request of a contentselected from the content list from the external device, that receivedthe content list sent from said image capturing apparatus, sends therequested content back to the external device.
 3. The apparatusaccording to claim 1, wherein said list generating unit determines abase recording medium upon integrating the storage location informationof the identical image data based on the amount of image data and anaccess speed for each recording medium.
 4. The apparatus according toclaim 1, wherein when identical image data are recorded in the pluralityof recording media, said list generating unit describes, in the contentlist, the representative storage location information to designate arecording medium with a highest access speed.
 5. The apparatus accordingto claim 1, wherein when a request for identical image data stored inthe plurality of recording media is received from the external device,said recording and reproducing unit reads out the requested image datafrom the recording medium with a highest access speed of the recordingmedia which store the identical image data.
 6. The apparatus accordingto claim 1, wherein said list generating unit generates the content listat a start-up timing of said image capturing apparatus.
 7. The apparatusaccording to claim 1, wherein said list generating unit updates thecontent list when the image data in the recording medium are updated. 8.The apparatus according to claim 1, wherein said list generating unitgenerates the content list of image data included in all recording mediaattached or connected to said image capturing apparatus.
 9. A contentmanagement method in an image capturing apparatus which comprises aconnection unit adapted to detachably connect a plurality of recordingmedia which includes at least one of internal recording media and atleast one of external recording media, the internal recording media andthe external recording media having various access speeds, an imagecapturing unit adapted to capture an object and generate an image dataof the object, a recording and reproducing unit adapted to record theimage data into the plurality of recording media, and read out the imagedata from the plurality of recording media, a list generating unitadapted to generate a content list which describes a list of image datastored in the plurality of recording media, and describes, in the list,storage location information of each image data stored in the pluralityof recording media, and a communication unit adapted to communicate withan external device and sending the content list to the external device,said method comprising: a step of checking if the image data stored inthe plurality of recording media include identical image data; and astep of generating, if the identical image data are detected, thecontent list which is registered as a representative storage locationinformation by which the storage location information of the identicalimage data are integrated with one piece of storage location informationfrom among the storage location information of the identical image datastored in the plurality of recording media, wherein the representativestorage location information indicates a download path to download theidentical image data stored in the plurality of recording media at thehighest speed.
 10. A program stored on a non-transitorycomputer-readable medium, said program configured to execute on acomputer the steps of the content management method according to claim9.